Jews try to conceal “ancient biblical beliefs,” which prescribe that they “kill children and collect their blood, in order to knead it into the bread that is eaten on Passover.”

That statement doesn’t come from a medieval German monk criss-crossing Europe preaching to the anti-Semitic speaking circuit. A Hamas official articulated it on Nov. 26, 2015, reports the Times of Israel, and compared present-day Israeli violence with the charge of Jewish anti-Christian murder and cannibalism. He seemed unaware, or unconcerned, that the indictment was and is a myth.

“This is the killing of a Palestinian child in order to collect his blood, and knead it into the bread they eat. Today, they are trying to say that these things never happened, and that it was a joke or a lie, but these are the facts of history. Anyone reading about their history will find this there,” the official added, according to a Middle East Media Research Institute translation.

A Touchstone of Historical Malevolence

Metaphorical charges of the term “blood libel” get batted around quite a bit in op-eds and on social media. Evidently the literal concept—which blatantly violates several iterations of the biblical injunction against eating blood (e.g. Deut. 12:23, Lev. 17:10-12, Lev. 19:26), “for therein lies the soul”—still endures as well, some nine centuries after the murder of one William of Norwich, which was blamed on the Jews.

“Now that Jewish ritual murder is no longer accepted as historical truth, there are understandable reasons to diminish or deny the past importance of the accusation,” E.M. Rose writes early on in The Murder of William of Norwich: The Origins of the Blood Libel in Medieval Europe. Both Christians and Jews are eager to avoid dwelling on the tragic past, she adds, and most prefer instead to focus on positive things, such as interfaith dialogue.

“That is why ritual murder and blood libel tend to be treated as characteristic of a distant medieval past. Yet the concept of the blood libel remains so emotionally charged and so deeply rooted in cultural memory that even today, whether visually or verbally, it endures as a touchstone of historical malevolence,” she writes.

The Origins of Anti-Semitism

The murder of the young Christian boy, William of Norwich, and the deposit of his tortured body in the woods is where it all began for blood libels, according to Rose’s book. As is generally the case when it comes to approaching the Middle Ages with modern eyes, it’s vital to try to imagine away many of the things that are taken for granted in contemporary culture.

Both Christians and Jews are eager to avoid dwelling on the tragic past, she adds, and most prefer instead to focus on positive things, such as interfaith dialogue.

Text, for example, is ubiquitous today—on billboards, sides of buses, newspapers, digital signs, clothing, etc.—but medieval people overwhelmingly couldn’t read, so a typical stroll down the street would have involved much less of a textual encounter.

It’s important to remember this when approaching medieval charges leveled against the Jews. When Jews were accused of murdering Christian children by drowning them in wells, one can imagine Sherlock Holmes or Columbo on the scene, studying knowingly the otherwise-invisible trail of clues. But medieval legal and religious records show that young corpses were often discovered in rivers and wells.

“Often one hears of such children, who survived parental neglect only to be rescued by some saint. Many other children fell or were hurled into fishponds, rivers, and wells, in some cases by family members or other adults,” Rose writes. “It is evident from miraculous stories of children’s rescues that medieval families faces a hazardous world: children fell into wells, ponds, and buckets, and drowning is the accident most often noted by papal notaries.”

So common were childhood drownings in the Middle Ages, she continues, that “the mere appearance of a drowned corpse should not attract undue attention from modern historians.” Yet Jews were accused of crucifying a Christian child in the French city of Blois in 1171 and of throwing the body into the Loire River; they were charged with drowning Robert of Bury in the 12th century; and when Hugh of Lincoln was found dead in an English well in 1255, that too was blamed on Jews.

The Root of All Evil

It’s also vital to remember that there was financial incentive to blame deaths on Jewish neighbors. As Rose illustrates several times, a martyred saint meant relic-status remains, and relics drew pilgrims. Those coming on religious pilgrimage to see a martyred saint, particularly a young innocent, came of course with their purses, and there was no lack of fees (lodging, food, entrance fees, etc.) that could be levied on those pilgrims.

Another advantage to blaming Jewish neighbors for a ritual murder was the assumption of wealthy Christians that the entire Jewish community was culpable for the alleged actions of a single member.

Throngs of visitors, and their money, could make the difference for a cathedral between being able to launch a major building or renovation project, and risking becoming the equivalent of a ghost town when railroad tracks become rerouted.

Another advantage to blaming Jewish neighbors for a ritual murder, which Rose details in the book, was the assumption on the part of wealthy Christians that the entire Jewish community was culpable for the alleged actions of a single member, and part of the consequences would be the appropriation of Jewish property, or the forced forgiveness of loans to Jewish moneylenders.

Christians who went on crusade to the Holy Land often found themselves helplessly in debt to Jewish moneylenders—who were empowered to loan money with interest to Christians, whose beliefs precluded entering that business—particularly if they didn’t realize financial gains in crusade spoils.

“Crusade preparation and financing, as much as the crusades themselves, effected major changes in northern Europe on many levels: personal, institutional, and national,” Rose writes. “The costs of crusading could be crushing.”

Nevermind the irony of crusading Christians, whose religious zeal was often anti-Semitic even if it was primarily directed at Muslims in the Holy Land, borrowing money from Jewish moneylenders. Irony is often overlooked for business purposes. What’s clear, in Rose’s telling, is that public (Christian) opinion about Jewish moneylenders in struggling, post-crusade financial times may have led many to think that murdering Jewish moneylenders would be overlooked, or even applauded.

Christian opinion about Jewish moneylenders in struggling, post-crusade financial times may have led many to think that murdering Jewish moneylenders would be overlooked, or even applauded.

“English magnates and rulers knew all too well how to extract money and loans from Jews. During the civil war Empress Matilda demanded money from the Jews of Oxford. On reclaiming the town, Stephen threatened to torch Jewish homes in Oxford (and in 1141 actually did burn at least one, perhaps with its inhabitants inside) in order to raise more than three times as much as she had claimed,” Rose writes.

When one Jewish merchant named Abraham refused to pay a tax that King John levied on Jews in 1210, Rose adds, he was imprisoned in Bristol Castle and his teeth were removed, one per day, until he gave in eight days later and paid “the enormous sum of 10,000 marks.”

A Pernicious and Long-lasting History

All of this is important to consider when approaching the story of William of Norwich, a leatherworking apprentice who was discovered dead in March 1144. A young man, William’s body was left in the woods. England was in the thick of a horrifying civil war at the time, and the fighting in the region surrounding Norwich was fierce. Finding corpses, even tortured and mutilated ones, was hardly unusual. But as Rose notes, much of what is “known” about the death and the ensuing investigation comes from “The Life and Passion of Saint William of Norwich,” which the Benedictine monk Thomas of Monmouth (she calls him “Brother Thomas”) published after two decades of research, in 1170.

A young man, William’s body was left in the woods. England was in the thick of a horrifying civil war at the time. Finding corpses, even tortured and mutilated ones, was hardly unusual.

As Thomas tells it, William was pursuing what he thought was a promising job with the archdeacon only to be lured into a prominent Jew’s home.

“At the direction of the homeowner, one of Norwich’s leading bankers, William was secretly held, subjected to ‘all the tortures of Christ,’ and finally murdered,” Rose writes, channeling Thomas. “According to Thomas, after the Jews had crowned William with thorns, tightened a knotted rope around his head and placed a gag in his mouth, they took the young man’s mutilated body out to the woods and hung it up.”

Brother Thomas, whose own incentives to be the chronicler of the canonization of an alleged saint ought to be at least considered, stated that Jews mean to imitate and mock the crucifixion in their treatment of William. That, it turns out, is consistent with other charges, primarily on the Jewish holiday of Purim, that Jews crucified Jesus, and even burned the almost voodoo dolls in effigy.

That claim, and quite a few others, are detailed at length in this book, which doesn’t sacrifice readability for its thoroughness. It takes more than 400 pages to detail how the unlikely case of William of Norwich’s corpse became prominent enough to forge the broader blood libel claim, which still endures today in the statements of Hamas and the rising number of anti-Semitic groups plaguing the Middle East as well as the West.

But if one line of Rose’s has to suffice, it comes early on: “The claim that Jews killed children and obtained their blood was to have a pernicious and long-lasting history, and left its mark in the realms of both popular imagination and elite opinion.”

A Washington DC-based reporter, Menachem Wecker holds a master’s in art history (medieval and Renaissance Europe) from George Washington University.